In India, neem ingredients are found in many popular consumer goods. Neem oil, for instance, has been a major ingredient in soaps for at least 50 years. Its antiseptic properties have been used to particular advantage in the manufacture of special medicated soaps and toothpastes. In addition, pharmaceutical preparations—emulsions, ointments, poultices, and liniments, as well as cosmetics such as creams, lotions, shampoos, hair tonics, and gargles—have been prepared. The latest cosmetic preparations are entirely free of the odor that previously restricted neem oil's use. (Agricultural Research Service, USDA)
cold-pressed oil, but it also goes into certain soaps and consumer products.
Purifying neem oil is an elaborate and costly process at present. In one method, the smelly sulfur compounds are distilled off, which frees the oil from both odor and susceptibility to rancidity (because it also removes the free fatty acids). This process has long been used industrially.
As an alternative to pressing out the oil, the kernels can be extracted first with alcohol and then with hexane.2 Alcohol removes the bitter and odoriferous compounds; hexane recovers the oil. This stepwise extraction upgrades both meal and oil. On the other hand, it requires